Primitive and Composite Events in NAOS
نویسندگان
چکیده
This paper focuses on the event component of the NAOS(Native Active Object System) active rule system. It rst gives an overview of the system and then presents the main concepts of the event model proposed for describing primitive and composite events. NAOS primitive events are of diierent granularities: events related to update operations on atomic and complex values, to method calls, to programs, transactions and applications executions. NAOS composite event types are deened using primitive event types and the of the composite events is based on the semantics of the proposed operators and on the notions of context of detection and validity interval. These notions are central especially for event types containing negations and strict disjunctions. The paper also presents the detection process for both kinds of events. It discusses the way this process has been implemented and interacts with the rule processing mechanism. Dans cet article, nous pr esentons la partie Ev enement du syst eme de r egles actives NAOS (Native Active Object System). Nous donnons une pr esentation g en erale du syst eme puis nous d ecrivons le mod ele d' ev enements primitifs et composites. Dans NAOS, les ev ene-ments primitifs peuvent ^ etre de dii erentes granularit es : ev enements li es a des op erations de mises a jour d'objets ou de valeurs atomiques ou complexes, a des appels de m ethodes, a l'ex ecution de transactions, de programmes et d'applications. Les ev enements composites sont construits r ecursivement en appliquant des op erateurs (disjonction, conjonction, s equence, it eration, n egation) a des ev enements primitifs ou composites. La s emantique des ev enements composites est bas ee sur la s emantique ds op erateurs et sur les notions de contexte de d etection et d'intervalle de validit e. Ces notions sont centrales pour les types d' ev enements contenant des n egations et des disjunctions strictes. L'article pr esente egale-ment le processus de d etection des ev enements primitifs et composites. Il discute de son implantation et de ses interactions avec le processus d'ex ecution des r egles. Ev enements primitifs et composites, D etection d' ev enements.
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